Despite their many environmental and energy savings advantages, radiation-curable compositions are used successfully in limited commercial applications. It would be desirable, therefore, to provide radiation-curable compositions capable of producing coatings having performance characteristics that might render the compositions desirable for use in applications that, heretofore, have rarely, if ever, employed radiation cure technology. Such performance characteristics include, for example, a smooth pleasing appearance suitable for, among other things, automotive applications, flexibility, adhesion to various substrates and coatings, resistance to scratch and mar, and exterior durability. Moreover, it would be desirable to provide such compositions that can be embodied as a one-component composition, and can be cured rapidly via radiation in an air environment.